To stop anthropogenic climate change, is it necessary to stop extracting petroleum and start pumping carbon under ground?

Question

The amount of carbon (C) on Earth is constants. As far as i understand, all carbon that is not found in the atmosphere or the oceans in the form of CO₂ or CO is stored either in the biomass (plants, animals, including humans, bacteria, mushrooms, etc.), or in fossils and fossil fuels (coal, petroleum, natural gases), or in non-organic form as graphite and diamonds. Is this correct? Does it follow that the only way to stop anthropogenic climate change and decrease the amount on CO₂ in the atmosphere is to stop extracting fossil fuels and to start converting CO₂ from the atmosphere into graphite or diamonds or into some form of petroleum and pump it back under ground?

I have asked a related question about carbon distribution on Earth.

Answer 1

Summary

Most of the remaining stocks of hydrocarbons (coal, natural gas, oil) will have to remain unburnt. In almost all cases, that will mean leaving them in the ground. We already have proven technology to prevent new emissions of anthropogenic greenhouse gas emissions, and in most cases, the technical and economic barriers are solved: the remaining problem is purely political.

Let's make sure we're talking about the same thing

Let's get our terminology straight first. The big issue is rapid climate change; and we can do something about that, because the current rapid climate change we are starting to experience, is anthropogenic - it is human-caused. So, "climate change" here refers not to historic natural processes over thousands to millions of years, but the present anthropocentric-induced processes that are happening over decades. That is the most common usage of the phrase these days, but it still can be useful to state it explicitly once in a while so that we know we are discussing the same thing.

Stocks and flows

Climate change is a result of changes in the stock of greenhouse gases in the atmosphere.

Those stocks have increased a lot over the last 180 years or so, and are continuing to change, because we've messed about with the flows. In particular, we've increased the rate of emissions from sources, without increasing the rate of take-up of sinks.

The bathtub analogy: we've opened the bath taps further, so water's flowing in faster. But we haven't widened the drain, so the level of water in the bath is rising, and soon will overflow and flood the house. It's not the rate at which water enters the bath that's the problem in and of itself: it's the level of water in the bath, and that's rising quickly because the inflow is much faster than the outflow. Similarly, what matters for climate and climate change is the level of greenhouse gases in the atmosphere, and the level of CO₂ absorbed into the oceans.

Even if new net emissions went to zero this year (technically impossible without the collapse of human civilisation, which would rather defeat the whole exercise), we'd still see increasing heat content of the Earth over the next few years, as things move towards equilibrium, based on the current levels of greenhouse gases which represent a historic increase over the levels that prevailed over the last few thousand years during which human civilisation has developed.

So, to prevent further climate change, we have to balance out sources and sinks. So we can do either, or a combination, of two things: we can decrease the rate of emissions from sources down to the level where existing sinks can absorb them; and we can increase the rate at which sinks absorb.

Reducing sources

Stopping burning fossil fuels is the easiest and simplest way to decrease the rate of emissions. To the best of my knowledge, we now have alternatives for almost all of the major emissions sources, with the possible exception of methane emissions from livestock farming. Some are very well-established, like hydro and onshore wind electricity generation. Some are maturing quickly, like PV, offshore wind. Some are successful in the lab, and ready to move to commercial-scale prototypes, such as decarbonised production of steel, clinker, and liquid hydrocarbons.

Increasing sinks

Carbon sequestration is one way to increase the sinks. It's been trialled at small scale, and remains problematic. The way that's been done so far is to pump the carbon dioxide underground. At the moment, no business has been willing to accept the open-ended liability that is posed by the risk of leakage. So at the moment, the market is saying that this is not a viable technology. That might change. It's also worth noting that at the moment, the market also wants to use CO₂ sequestration as a means of extracting even more oil (Enhanced Oil Recovery, EOR), which just makes the whole problem worse.

One way that is fast, effective and affordable is increasing the amount of carbon in biomass. Reforestation and afforestation are two ways to do this, and would help reverse a lot of the human-caused loss of forest ecosystems, if done well.

Answer 2

No, we do not need to stop extracting petroleum, we need to stop burning petroleum, as well as other fossil fuels, because combustion converts solid C to gaseous C, and hence goes up to the atmosphere, increasing the amount of greenhouse gases that warm the planet.

No, we do not need to convert existing CO₂ into diamonds. Plants are pretty good taking up CO₂ from the atmosphere, and storing the C as wood, that goes later into the soil as plant litter, where it can be stored long-term (and over millions of years may even become diamonds, petroleum or coal!). There are C losses as CO₂ into the atmosphere, via either plant or soil respiration, but that is another wide topic. To be more precise, terrestrial plants and oceans remove each year more than half of the CO₂ we emit into the atmosphere, for free!

Answer 3

Shortly:

Yes, stopping extracting fossil fuels from the deep soil and starting pumping carbon into the deep soil is a feasible and relatively easy solution to stop global warming.

Full explanation:

By assuming that anthropogenic global warming is caused by the rise of greenhouse gases concentration in the atmosphere (let's say mainly CO₂),
in order to stop it, it is necessary to reset it from its actual value (about 415 ppm in February 2020) to the one it was before industrial revolution (around 250 ppm).

This leads to the fact that greenhouse gases emissions related to anthropogenic activities must not just stops, but it has to turn negative, in order to remove the excess of greenhouse gases from the atmosphere.

Given the fact that we can identify 8 big carbon reservoirs on our planet and 7 big carbon fluxes among these reservoirs,
every activity that contributes to redistribute the fluxes so that, globally, more carbon is drained from the atmosphere and transferred into another reservoir until the atmosphere greenhouse gases concentration reaches 250 ppm, it is a potential solution to global warming.